ICAM: integrated cellular and ad hoc multicast

Abstract

In third generation (3G) wireless data networks, multicast throughput decreases with the increase in multicast group size, since a conservative strategy for the base station is to use the lowest data rate of all the receivers so that the receiver with the worst downlink channel condition can decode the transmission correctly. This paper proposes ICAM, Integrated Cellular and Ad hoc Multicast, to increase 3G multicast throughput through opportunistic use of ad hoc relays. In ICAM, a 3G base station delivers packets to proxy mobile devices with better 3G channel quality. The proxy then forwards the packets to the receivers through an IEEE 802.11-based ad hoc network. In this paper, we first propose a localized greedy algorithm that discovers for each multicast receiver the proxy with the highest 3G downlink channel rate. We discover that due to capacity limitations and interference of the ad hoc relay network, maximizing the 3G downlink data rate of each multicast receiver's proxy does not lead to maximum throughput for the multicast group. We then show that the optimal ICAM problem is NP-hard, and derive a polynomial-time 4-approximation algorithm for the construction of the multicast forest. This bound holds when the underlying wireless MAC supports broadcast or unicast, single rate or multiple rates (4ð1 þ Þ approximation scheme for the latter), and even when there are multiple simultaneous multicast sessions. Through both analysis and simulations, we show that our algorithms achieve throughput gains up to 840 percent for 3G downlink multicast with modest overhead on the 3G uplink.

Scalable Video Multicast in Hybrid 3G/Ad-Hoc Networks

“…The effect of ad-hoc path interference is taken into consideration. ICAM [8] developed a close-to-optimal algorithm for the construction of the multicast forest in the integrated cellular and ad-hoc network. In an approach different from these two systems, Sinkar et al [9] proposed a novel method to provide QoS support by using an ad-hoc assistant network to recover the loss of multicast data in the cellular network.…”

A joint multicast/D2D learning-based approach to LTE traffic offloading

“…Thus, the worst channel among all the receivers dictates performance. It follows that an increase in the number of users in the multicast group boosts the probability that at least one user experiences bad channel conditions, degrading the overall throughput [8].…”

“…Bhatia et al, proposed the use of D2D communications to improve performance of multicast in 3G cellular networks [8]. A multihop ad hoc network is modeled analytically.…”

Distributed Source Coding for WWAN Multiview Video Multicast with Cooperative Peer-to-Peer Repair

“…We stress that our assumption of available multi-homing capable devices (each has multiple network interfaces to connect to orthogonal delivery networks simultaneously) is a common one in the literature [7], [8], [9], where different optimizations are performed exploiting the multi-homing property. [7] shows that aggregation of an ad hoc group's WWAN bandwidths can speed up individual peer's infrequent but bursty content download like web access.…”

“…[7] shows that aggregation of an ad hoc group's WWAN bandwidths can speed up individual peer's infrequent but bursty content download like web access. [8] proposes an integrated cellular and ad hoc multicast architecture where the cellular base station delivered packets to proxy devices with good channel conditions, and then proxy devices utilized local ad hoc WLAN to relay packets to other devices. [9] shows that smart striping of FEC-protected delay-constrained media packets across WWAN links can alleviate single-channel burst losses, while avoiding interleaving delay experienced in a typical single-channel FEC interleaver.…”